population growth and change - kendall hunt … 1 population growth and change 3 percentage rate....

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CHAPTER 1

Population Growth and Change

Key Terms

population growth

basic demographic equation

rate of natural increase

rate of population growth

doubling time

carrying capacity

population projections

mathematical methods

component methods

genocide

baby boom

Our aim in Chapter 1 is to place the present world population into a broader historical perspective and then to consider current and future population trends. Only after we

have seen where we have been, and how we got to where we are, can we begin to ponder our demographic future.

Measuring Population Growth and ChangeAny understanding of the ways in which population processes operate to shape or alter the size or composition of a region’s population requires a knowledge of various measures of population growth and change.

The Basic Demographic EquationThe most fundamental characteristic of any population is its size. An area’s population may be increased either by a birth within the area or by the migration into the area of a person from another area. Similarly, the population may be decreased either by the death of someone within the area or by the migration of someone from the area out to another area. Thus, the primary population processes are births, deaths, and migration. These basic demographic processes may be combined to produce the following equation:

FP � SP � B � D � I � O,

where FP � fi nal population, some time interval beyond SP, SP � starting population,

Population growth is the change in population

over time, and can be

quantifi ed as the change

in the number of indi-

viduals in a population

per unit time.

ch01.indd 1ch01.indd 1 6/26/13 6:53 PM6/26/13 6:53 PM

Population Geography2

B � births during the interval, D � deaths during the interval, I � in-migration during the interval, and O � out-migration during the interval.

It is easy to see why demographers have sometimes referred to it as the “basic demo-graphic equation.”

The Rate of Natural IncreaseFor any given population the rate of natural increase (RNI) equals the crude birth rate (CBR) minus the crude death rate (CDR). Thus

RNI � CBR � CDR.

The crude birth rate is the number of births per 1,000 population in a one year period, or

CBR � (B/P) � 1,000,

where B � number of births in one year and P � mid-year population.

In 2011 the crude birth rate for the world was about 20 per thousand and for the United States it was approximately 13 per thousand. The crude birth rate is infl uenced to some degree by the age and sex structure of a population.

The crude death rate is the number of deaths per 1,000 population in a one year period, or

CDR � (D/P) � 1,000,

where D � number of deaths in one year and P � mid-year population.

In 2011 the crude death rate for the world was about 8 and for the United States it was around 8. The crude death rate is considerably more affected by the age structure of the population than is the crude birth rate, so comparisons among countries need to be done with caution. This should be immediately apparent when you consider that the world rate and the rate in the United States are the same.

Because the crude birth and death rates are both expressed per 1,000 population, it is obvious that the rate of natural increase will also be expressed in units per 1,000 population—births minus deaths. Since the crude birth rate for the world was 20 and the crude death rate was 8, the world’s rate of natural increase for 2011 was equal to 20 minus 8, or 12 per thousand. Similarly, for the United States the rates were 13 and 8, respectively, and the rate of natural increase in the United States in 2011 was 13 minus 8, or 5 per thousand. Note that the rate of natural increase is not necessarily the same as the rate of population growth because the effect of migration is not included in the former. For the world, the rate of natural increase equals the rate of popula-tion growth because migration to and from the earth is currently nonexistent. For the United States, however, the rate of natural increase is well below the actual rate of population growth because of a sizable annual net immigration (which is the subject of considerable debate today).

The Rate of Population GrowthThe rate of population growth is a measure of the average annual rate of increase for a population. Barring migration, it is possible to convert the rate of natural increase to the natural rate of population growth by simply converting the rate per 1,000 to an annual

The most fundamen-

tal characteristic of

any population is its

size.

Primary population

processes are births,

deaths, and migration,

which combine to pro-

duce the basic demo-graphic equation.

Rate of natural increase is the crude

birth rate minus the

crude death rate of a

population.

The rate of popu-lation growth is a

measure of the average

annual rate of increase

for a population.


CHAPTER 1 Population Growth and Change 3

percentage rate. For the world the rate of natural increase was 12 per thousand, which is equivalent to an annual rate of population growth of 1.2 percent. Keep in mind, however, that most of the time migration must be considered, so the rate of population growth will usually differ from the rate of natural increase. To some extent the relative effects of natu-ral increase and migration are inversely related to the size of the area under consideration. Whereas at the world scale migration plays no part at all in population growth, at the local scale migration may even be more important than natural increase in determining the overall rate of population growth.

In the United States example the rate of natural increase amounts to an annual growth rate of 0.5 percent. Actually, the 2011 rate of population growth for the United States was closer to 1.0 percent. The difference between these two rates results from net immigration. In other words, 50 percent of the growth in the United States, population in 2011 was due to natural increase and 50 percent was due to net immigration.

Doubling TimeThe doubling time of a population is the number of years that would be required for a population to double in size, assuming that the population continues to grow at a given annual rate. This growth is analogous to the growth of money in a bank savings account. In both cases the “interest” is compounded. Without going into detail, it is possible to closely approximate the doubling time for a population by dividing the annual rate of population growth into the number 70. Thus, for the world, growing at 1.2 percent annu-ally, the time required to double the present population would be 58 years. This assumes, of course, that the 1.2 percent growth rate continues over the entire period. For the United States, growing at 1.0 percent, the doubling time would be around 70 years.

World Population GrowthThis section is concerned with the growth of the human population from prehistoric times to the present. Once we get into the twentieth century the focus shifts from the total world population to regional patterns of growth—mainly to the current division of the world into less developed (mainly poor) and more developed (mainly rich) regions—and to the differences between these regions with respect to population growth. We gener-ally use the terms less developed and more developed regions with reference to levels of economic development—occasionally less developed countries may also be referred to as Third World countries.

Brief Overview of World Population GrowthIn order to understand the current world population situation, as well as future prospects for the world’s ever-increasing numbers, it seems worthwhile fi rst to discern how it is that the population reached its current level—a world of 7 billion people growing at an average annual rate of about 1.2 percent. Those fi gures suggest that each year around 84 million people are added to what many already perceive to be an overcrowded planet. Every four years more people are added to the world’s population than currently live in the entire United States. Most geographers and demographers believe that this rate of growth cannot continue indefi nitely. As Berelson and Freedman (1974, 3) noted more than three decades ago, “The rate of growth that currently characterizes the human popu-lation as a whole is a temporary deviation from the annual growth rates that prevailed during most of man’s history and must prevail again in the future.” This recent period of rapid population growth is unique in demographic history, both in terms of the rate of population growth and in terms of the absolute size of the world’s population. The world’s population nearly quadrupled during the twentieth century, from 1.6 billion in

The doubling time

of a population is the

number of years that

would be required for a

population to double in

size, assuming that the

population continues to

grow at a given annual

rate.



1900 to 6.1 billion in 2000. Population geographers and demographers do not expect that to happen again.

For most of human demographic history, population growth was exceedingly slow; the annual rate of increase probably did not reach 0.1 percent (a doubling time of about 700 years) until sometime in the seventeenth century, after which it began to accelerate. This acceleration was gradual at fi rst, but it became more noticeable after 1750.

Our cur rent knowledge of historical populations remains conjectural. Clever demo-graphic detectives, using whatever clues they can uncover (from archaeological excavations to early church baptismal, marriage, and death records), have pieced together the story of the human population’s slow but inexorable expansion in both numbers and occupied ter-ritories. Our knowledge of historical population sizes and growth rates remains speculative because censuses and other organized and systematic collections of population data were nearly nonexistent before the middle of the eighteenth century. Earlier censuses had been taken in a few places, but their data were controversial at best. Even today reliable statistics don’t exist for perhaps half of the world’s population.

Estimates of population numbers in prehistoric times vary considerably and are gener-ally made on the basis of assumptions about the carrying capacity of the land—its capac-ity to sustain a given human population at a given level of technology—and the distribution of the human population. Cohen (1995a) and others have tried to model human carrying capacity of the earth, but there has generally been little agreement among different approaches, partly because of the complexity of human societies and cultures. Hopfenberg (2003, 109) used food supply data in a logistic model and concluded: “That food supply data adequately fi ts the logistic model of human population dynamics provides evidence that, consistent with ecological notions typically applied only to nonhuman species, human population increases are a function of increased food availability.” This fi ts well with Cohen (1995b, 35), who earlier observed that “The ability to produce food allowed human numbers to increase greatly and made it possible, eventually, for civilizations to arise.”

Speaking of numbers, this and other books on population are full of them, so let us digress for a minute and talk about them. On May 30, 2013, according to the Census Bureau, the population of the United States was 315,949,324 and the population of the world was 7,088,560,200. What precision! But don’t take these numbers, or others like them, too seriously. Most of the above digits mean nothing, though they demonstrate how nice it is to have computers around to generate them. Round them off to 316 million and 7.1 billion and you have lost no accuracy–the accuracy is only apparent to start with. Furthermore, such numbers can be manipulated

easily while forgetting that they represent real lives. We encourage you to remember what Cohen (1995b, 20) pointed out, that “Uncertainty does not render statistical numbers worthless; even with uncertainty, statistical numbers are indispensable. They are often far more informative than verbal descriptions or intuitive hunches. But every statistical num-ber should enter your consciousness with a penumbra of doubt.” In other words, don’t take numbers for granted–look at them carefully, think about how precise they might be, and keep in mind that there may be considerable uncertainty surrounding them. Numbers are necessary for our discussions, but it is also necessary to view them with a touch of suspicion.

Deevey (1960) estimated that the world’s population around one million years ago was about 125,000. According to his estimates, this population grew very slowly to approximately 3.34 million 25,000 years ago and to 5.32 million 10,000 years ago. By A.D. 1, Deevey and others estimate, the world’s population was in the neighborhood of 250–300 million. At that time the average annual rate of increase was probably on the order of 0.05 percent. At that growth rate it would take about 1,400 years for a population to double, compared to a doubling time of about 58 years for today’s population.

Even today reliable

statistics don’t exist

for perhaps half of the

world’s population.

The carrying capacity of land is its capacity to

sustain a given human

population at a given

level of technology.

“The ability to produce

food allowed human numbers

to increase greatly and made

it possible, eventually, for

civilizations to arise.”



The world’s population did not reach its fi rst billion until sometime around 1820. By then the annual rate of growth had increased tenfold to roughly 0.5 percent. Though all of human history had been required to reach this fi rst billion, only 110 years were required to add the next billion; by 1930 there were 2 billion residents on our planet. In only 45 years this 2 billion doubled to the 1975 population of 4 billion, and by 1987 the world’s popu-lation had grown to 5.0 billion. Only twelve years later the next billion had been added. As a species, we have certainly demonstrated our capacity for successful reproduction, but it may well be time for us to restrain ourselves before we fi nd a way to destroy our own ecological niche (though not the earth—it could get along quite well without us, as it did for most of its history). As Ornstein and Ehrlich (1989, 45) noted:

Increasing numbers is a “goal” of all organisms. But never before has there been an “outbreak” of a single species on such a global scale. Unfortunately it is not yet clear how enduring our unprecedented triumph will be, because it has created an unprecedented paradox: our triumphs can destroy us. As people strive to increase their dominance even further, they are now changing the earth into a planet that is inhospitable to civilization.

Geographer Crispin Tickell (1993, 220) noted that “All previous civilizations have col-lapsed.” Though he recognized variations on the general theme, he suggested that each early civilization suffered from a fatal combination of population, resource, and environmental variables that turned unfavorable at some point. Furthermore, Tickell (1993, 220) added that:

The prime engine of the recent dizzymaking rise in the human population and change generally is the industrial revolution. We have the misfortune to be per-haps the fi rst generation in which the magnitude of the global price to be paid is becoming manifest.

Cohen (1995b, 367) put it this way: “The human population of the Earth now travels in the zone where a substantial fraction of scholars have estimated upper limits on human population size.” A look at how the world population has grown may help us better under-stand where we are today and how many more people are likely to be added to Earth’s population in the decades ahead.

Warning!

The study of population is based largely on the collection and analysis of demo-

graphic data. These data vary considerably in reliability, so it is necessary to pro-

ceed somewhat cautiously, to develop a healthy skepticism about population

information and its interpretation. In an informative article, Bouvier (1976, 8–9)

suggested the following warnings that you should certainly heed:

• Warning 1: Do not use growth rates to indicate changes in birth rates. • Warning 2: Do not use natural increase to indicate population growth,

except in those areas where migration is nonexistent.

• Warning 3: Do not confuse numerical growth or decline with rates of

population growth or decline. • Warning 4: Do not take population fi gures as gospel truth, especially if

they come from areas with less than adequate data-gathering facilities.

Each of these warnings should be considered carefully; errors in demographic

thinking often result from a failure to consider one or more of them.



Figure 1–1 provides a graphic illustration of human population history. The slow growth that characterized so much of the early history of humankind gives way, fi rst grad-ually, then much more rapidly, to increased rates of population growth. These changes in growth rates involved alterations of both birth rates and death rates, with an emphasis on the latter; alterations that were in turn linked to sweeping changes in the socioeconomic fabric of societies.

Figure 1–2 shows past population growth on a logarithmic rather than an arithmetic graph, allowing us to focus more on changes in the rates of increase. The contrast with Figure 1–1 is both striking and suggestive. Rather than a single period of population growth, three periods of relatively rapid demographic increase become apparent, each of them followed by a slowing of growth rates. Deevey (1960) argued that each of these periods of accelerated population growth was a response to a revolution in which the

0

1

2

3

4

5

6

7

8

9

10

200 400 600 800 1000 1200 1400 1600 1800 2000 2200

Bill

ion

s

Year

Figure 1–1 Arithmetic Growth of World Population

Source: McEvedy and Jones,1978; United Nations 2011.

Figure 1–2 Logarithmic Growth Curve for World Population from

1,000,000 Years Ago

Source: Adapted from “The Human Population” by Edward S. Deevey, Jr., Scientifi c American. September 1960.



earth’s carrying capacity was dramatically increased. Each of these revolutions in carrying capacity can be viewed as a diffusion process, radiating outward from one or more origins to gradually encompass the inhabited world. The earliest of the three revolutions was the toolmaking or cultural revolution; the second was the agricultural revolution; and the third was the scientifi c-industrial revolution, which continues today.

The implications of Figures 1–1 and 1–2 for future population growth are dramati-cally different. Figure 1–1 implies a continuing rapid increase in the size of the world’s population (perhaps followed by a catastrophic crash?), whereas Figure 1–2 suggests that the world should experience a tapering off of growth rates as the world population adjusts to the current technological levels and their concomitant limitations on population expan-sion. Barring another major revolution that would again expand the earth’s carrying capac-ity, Deevey’s interpretation of population history implies a slowing of world population growth, one that we are already beginning to see. The world’s population growth rate reached a peak sometime in the late 1960s at around 2.1 percent, from which it has dropped gradually to a level of about 1.2 today. Though the direction of change is encour-aging, we need to keep in mind that it only represents a change in doubling time from about 33 years to 58 years. Furthermore, given the size and youthfulness of the planet’s population, absolute annual population increases (as opposed to the rate of increase) will remain large for many years.

You might wonder, as others have done, how many people have ever lived on our planet. Demographer Carl Haub (2002) estimated an answer. By making a number of “guestimates” about populations, births, and deaths in the past, he concluded that 106,456,367,669 people had been born by 2002. Of those births, about 5.8 percent, 6.125 billion, were still living at the time. By 2008 perhaps another 800 million births had occurred and the total population had passed 6.6 billion. In 2011, it is estimated that 108 billion people have ever lived on earth

The Three Major Periods of Population GrowthAs we have already noted, Deevey (1960) proposed that population growth occurred unevenly over time, mainly in conjunction with three major revolutions in human history—the cultural, the agricultural, and the scientifi c-industrial revolutions. These three major revolutions serve as the basis for subdividing our discussion of population growth into three discrete periods. This is appropriate because each of the revolutions must have opened up new possibilities for population growth, mainly because each one extended the earth’s carrying capacity. However, the availability of population facts decreases rapidly as we move back in time, hence the following discussion must be approached with a degree of caution.

The Cultural Revolution and Population GrowthIt was the emergence of primates, perhaps as early as 85 million years ago (Gugliotta, 2002), that set the stage for the gradual origin and spread of our own human population. The earliest primates, which probably overlapped the age of dinosaurs, were small (around two pounds) and ate mainly insects and fruit. At some point in time, perhaps eight million years ago, humans diverged from chimpanzees, our closest living relatives. It was a long road from there to where we are today, however, one still full of mysteries, potholes, ruts, and even evolutionary deadends.

The cultural, or tool-making, revolution occurred in prehistoric time. What knowl-edge exists of events in that era must be drawn primarily from the archaeological record. Seeking into the origin and evolution of the human population continues to occupy the time and energy of many researchers, mainly anthropologists. Periodically, new fi nds of

Population growth

occurred unevenly

over time, mainly

in conjunction

with three major

revolutions in human

history—the cultural,

the agricultural, and

the scientifi c-industrial

revolutions.



the skeletal remains of early hominids push back the frontiers of our knowledge to yet earlier times. The geographical search for early people has established an African origin.

Several pieces of archaeological evidence have pushed the frontier of hominid history farther back into the dawn of our evolutionary chronology. The earliest hominid on record so far, one similar in many ways to modern chimpanzees, is nearly seven million years old and goes by the name Sahelanthropus tchadensis, a name that recognizes its origin in Chad in the Sahel region of Africa. This region is well west of the Great Rift Valley in which most subsequent evidence of hominids have been discovered and suggests that human origins may have been geographically more widespread than has traditionally been appreciated. Around 5.5–5.8 million years ago Ardipithicus ramidus kadabba (a new genus) roamed parts of East Africa, as did Ardipithecus ramidus ramidus at least 4.4 million years ago. Meave Leakey’s (1995) Kanapoi fossils, found not far from Lake Turkana, extended Aus-tralopithicus afarensis back to about 4.1 million years ago.

Between Ardipithecus ramidus and Australopithecus afarensis, at an age of 4.2 to 3.9 million years ago, Leakey and Walker (1997) have added a new species, Australopithe-cus anamensis, based on further fossil evidence from sites at Kanapoi and Allia Bay.

Previously known skeletal remains uncovered in Africa suggested an age of 2.8 to 3.8 million years for Australopithecus afarensis, as exemplifi ed by “Lucy” (Johanson and Edey, 1981) and the “Dikika Baby” (Sloan, 2006), 1.6 to 2.2 million years for Homo habilis, and 1.4 to 1.7 million years ago for Homo erectus. Bipedalism was probably the earliest char-acteristic that separated hominids from their nearest relatives, the gorillas and chimpanzees. After that, increasing brain size is one of the primary features that distinguishes each one of the hominid groups from the next. However, as Ornstein and Ehrlich (1989, 37–38) have suggested, “. . . although the human brain appears to have enlarged rapidly (in geological time) in response to the pressures of culture, it does not seem likely that the brain crossed any real physical threshold that suddenly permitted new kinds of cultural activities.”

Perhaps our arrogant view of ourselves long colored the way in which we perceived our evolution from ape to hominid to modern people. Like other successful animal species, the line of humans, once separated from the apes fi ve or six million years ago, apparently went through considerable trial and error, made many false starts, and reached a few dead ends. Ian Tattersall (2000) argued convincingly that at least four kinds of hominids lived together within a single landscape in part of what is now northern Kenya about 1.8 million years ago. Though we may never know the degree to which they interacted with each other, Tattersall argues that Paranthropus boisei, Homo rudolfensis, Homo habilis, and Homo ergaster (also known as African Homo erectus) occupied the same geographical area at the same time. As Tattersall (2000, 61) phrased it, human evolution has not been a simple linear pattern:

Instead it has been the story of nature’s tinkering: of repeated evolutionary experi-ments. Our biological history has been one of sporadic events rather than gradual accretions. Over the past fi ve million years, new hominid species have regularly emerged, competed, coexisted, colonized new environments and succeeded—or failed. We have only the dimmest of perceptions of how this dramatic history of innovation and interaction unfolded, but it is already evident that our species, far from being the pinnacle of the hominid evolutionary tree, is simply one more of its many terminal twigs.

According to Wenke (1990), two scenarios currently set the stage for debate about the continued search for human origins. One of these scenarios suggests the migration of Homo ancestors, most likely Homo erectus, out of Africa some 1.5 million years ago, fol-lowed by gradual diversifi cation among scattered groups but at the same time a gradual evolution toward Homo sapiens among all the groups because of both common genetic

The cultural, or tool-

making, revolution

occurred in prehis-

toric time.

What knowledge

exists of events in

that era must be

drawn primarily from

the archaeological

record.



inheritances and similar adaptive pressures. The result of this fi rst scenario, as Wenke (1990, 137) described it, was “that they all converged at about 30,000 years ago as one species, Homo sapiens sapiens.” The other scenario begins in the same way, with the migra-tion of Homo ancestors out of Africa some 1.5 million years ago. This scenario d iffers after the initial migration by suggesting considerably more divergence among groups as they spread out and adapted to different environments. Following the second scenario, accord-ing to Wenke (1990, 137), the fi nal result is that “perhaps 140,000 years ago, Homo sapi-ens evolved in one place (probably Africa), and spread across the world, displacing most groups, driving some into extinction, and absorbing a small fraction of the others through intermarriage.”

In recent years the latter scenario has received considerable attention, not from archae-ological but from genetic evidence. Cann, Stoneking, and Wilson (1987) argued that the maternal lineage of all humans could be traced backed to a single African woman who was alive perhaps 200,000 years ago, a woman now referred to by many as “Mitochondrial Eve.” Their data were based on studies of mitochondrial DNA (deoxyribo-nucleic acid), which are only maternally inherited. These DNA then form the basis for a “molecular clock,” which in turn can be used to develop a branching tree. As Stringer (1990, 99) has noted, “One attempts to make a molecular clock by comparing genetic differences among various species or varieties within species and expressing their relatedness in a tree . . . then calibrates (or ‘dates’) the tree by comparing it with another group that diverged from the tree at a known date.” Studies since 1987 have tended to confi rm the African origin of “Mitochondrial Eve” and have given rise to considerable speculation about what that means for the Neanderthals (Stringer, 1990). Barinaga (1992, 686), citing increasing ques-tions that have been raised about the DNA methodology, noted that “. . . the root of the human tree has been thrown open to question once again.” Current criticism is focused primarily on how the mitochondrial DNA have been analyzed and whether or not these data can identify a geographic origin for our species. Excellent summaries of the two opposing views of evolution over the past 200,000 years are Wilson and Cann (1992) and Thorne and Wolpoff (1992). The earliest migration date must be pushed back because of the discovery of fossil remains found in Dmanisi, Republic of Georgia, that date back to 1.75 million years ago and provide clear evidence that Homo erectus or something similar had left Africa earlier than 1.5 million years ago.

In a review of these two competing hypotheses about our origin, Tattersall (1997, p. 67) wrote that “. . . my strong preference is for a single and comparatively recent origin for H. sapiens, very likely in Africa—the continent that, from the very beginning, has been the engine of mainstream innovation in human evolution. Additionally, Olson (2002, 28) noted that “. . . the genetic evidence available today points to a straightforward conclu-sion. According to our DNA, every person now alive is descended from a relatively small group of Africans who lived between 100,000 and 200,000 years ago.” The oldest fossil of a modern human found so far was discovered in Orno Kifi sh in Ethiopia, where it lived about 195,000 years ago. Put a different way, Olson (2002, 38) stated that “Everyone alive today is either an African or a descendant of Africans.” More recently, Shreeve (2006, 69) wrote that “DNA studies have confi rmed this opening chapter of our story over and over: All the variously shaped and shaded people of Earth trace their ancestry to African hunter-gatherers, some 150,000 years ago.” He goes on to suggest (2006, 69) that “Perhaps the most wonderful of the stories hidden in our genes is that, when unraveled, the tangled knot of our global genetic diversity today leads us all back to a recent yesterday, together in Africa.”

The emergence of anatomically modern humans, H. Sapiens, as the only surviving members of a long chain of trials and errors occurred recently—probably no more than 25,000 to 28,000 years ago. Before that, we know, for example, that 90,000 to 100,000



years ago in the region that now includes Israel, modern humans lived side-by-side with Neanderthals (whose reputations have been much improved as a result of recent research), though that group seems to have died out without spreading. In 2003 researchers reported some of the oldest known fi nds of skulls of modern humans. They were approximately 160,000 years old and were found in the proximity of a now-vanished lake in Ethiopia. This evidence puts the fossil evidence in line with the arguments of geneticists—an African origin for Homo sapiens between 150,000 and 200,000 years ago.

Despite the fi nd of early modern human fossils in Qafzeh, Israel, that were dated to nearly 100,000 years ago, most evidence today suggests that the successful migration of modern humans out of Africa and around the world began between about 70,000 to 50,000 years ago. As Shreeve (2006, 63) noted, “All non-Africans share markers carried by those fi rst emigrants, who may have numbered just a thousand people.” Likely paths were around the north of the Red Sea or across its southern opening (Shreeve, 2006). From there modern humans spread northwestward into Europe, north into what is now Russia, and east through Asia, reaching Australia by around 50,000 years ago. The New World was not populated by modern humans until about 20,000 years ago, or even less, when sea levels were low enough to allow people to cross between Siberia and Alaska.

Between 30,000 and 40,000 years ago modern humans appeared in Europe, where Neanderthals lived already. However, at least according to Tattersall (2000, 61), “Certainly the repeated pattern at archaeological sites is one of short-term replacement, and there is no convincing biological evidence of any intermixing in Europe.” In a period of perhaps 10,000 years the Neanderthals disappeared.

Wong (2000), however, identifi es some differences of opinion among anthropologists’ interpretation of the European confrontation between Neanderthals and modern humans. For example, anthropologist Fred Smith (cited in Wong, 2000, 107) tells us that “The likelihood of gene fl ow between the groups is also supported by evidence that Neander-thals left their mark on early modern Europeans.”

Near the end of 2004 a new skeletal discovery created a stir among anthropologists (Wade, 2004). The discovery was made on the Indonesian island of Flores, about 370 miles east of Bali. The bones were from an adult that would have been around 3.5 feet in height, lived on the island until about 12,000 years ago, and were not pygmy forms of modern people. Rather, they appeared to be downsized versions of Homo erectus. This discovery suggests that some of the earliest people to leave Africa may have lived for much longer than has been previously thought. These dwarf humans, assigned the name Homo fl oresiensis, but dubbed Floresians, were still around 20,000 years after Neander-thals disappeared, made stone tools, and lived among giant rats, pygmy elephants, and Komodo dragons. Nicknamed “Hobbit,” this small hominid created considerable con-troversy, with some arguing that it was some kind of dwarf or perhaps a case of micro-cephaly, but recent testing has ruled out the latter and found in favor of the separate species school.

We are still left with more questions than answers. It seems clearer all the time that the evolution of modern humans was a complex drama that unfolded over a period of some fi ve million years. Trial and error, numerous wrong turns, and dead ends led to the fi nal emergence and dominance of modern humans between 25,000 and 30,000 years ago. Tat-tersall argues that the fi nal defi ning characteristic that gave modern humans their edge over the Neanderthals may have been the development of language and an ability to form mental symbols. As he notes (Tattersall, 2000, 62), “We do not know exactly how lan-guage might have emerged in one local population of H. sapiens . . . . But we do know that a creature armed with symbolic skills is a formidable competitor—and not necessarily an entirely rational one, as the rest of the living world, including H. neanderthalensis, has discovered to its cost.” Whatever the particular advantages of modern humans were, there



is little doubt that McNeill and McNeill (2003, 4) were right when they com-mented that “What drives history is the human ambition to alter one’s condition to match one’s hopes.”

Though these debates will undoubtedly continue, perhaps it is more important at this point for us to consider Wenke’s (1990, 186) summary comment that “. . . we should also take note of the fact that even though we are physically very much like our ancestors of 12,000 years ago, we are enormously different culturally . . . in a cultural sense we are not at all the same species as the human hunter-gatherers of the late Pleistocene . . . to live a life for which evolution has shaped us—we should probably eat a varied diet, live closely in a small group, and walk a lot.”

As fascinating as such studies of early Homo and earlier ancestors may be, little is known of the numbers involved, though they were undoubtedly small. As Deevey (1960, 5–6) commented, “For most of the million-year period the num-ber of hominids, including man, was about what would be expected of any large Pleistocene mammal—scarcer than horses, say, but commoner than elephants.” Not only were the numbers small, but the rate of growth in these numbers must also have been exceedingly small. The growth of Homo sapiens sapiens prior to the agricultural revolution remained extremely slow. Hunting, fi shing, and foraging provided an existence, though undoubtedly a precarious one. Life was most likely “nasty, brutish, and short.”

Population densities on the eve of the agricultural revolution were low, and populations were vulnerable to environmental changes such as climatic fl uctua-tions. Estimates of population size are subject to wide margins of error and must be accepted with reservation; however, the order of magnitude seems reason-able. According to Deevey (1960), the world’s population 10,000 years ago was 5.32 million, though others have suggested that it might have been twice that number. Even if we accept 10 million, we’re talking about a small base from which we have grown in a relatively short time.

The Agricultural RevolutionAn exact date for the beginning of the agricultural revolution is impossible to set, but it is likely that incipient cultivation and domestication developed sometime around 10,000 B.C. in the Near East. A curious point about the beginning of agriculture revolves around the length of time that modern humans had been around (at least 140,000 years) before agriculture began to take root, so to speak. Why did it take so long, we might wonder? One answer, not completely agreed upon, is the better climate that developed at the end of the last Ice Age. Weath-erford (1994, 47) noted, for example, “Around the world, humans seem to have switched from foraging to farming because of the whole set of changes produced by global warming.” In writing about agriculture and the warming climate at the end of the last Ice Age, Flannery (2005, 61) argued that “It’s hard to avoid the feeling that the hostile ice age climate and its savage transition to the inter-glacial had, until then stymied this great fl owering of creativity and complexity.” Furthermore, he noted (2005, 63) that “The long summer that has been the last 8,000 years is without doubt the crucial event in human history.”

A reasonable scenario is that around 12,000 years ago hunter-gatherers began to settle along the shore of the eastern Mediterranean, exploiting local plants and animals, making seasonal hunting trips, and gradually becoming more sedentary. Archaeologists have confi rmed that by around 8,000 B.C. Jericho

“What drives history is

the human ambition to

alter one’s condition to

match one’s hopes.”

An exact date for the

beginning of the agri-

cultural revolution

is impossible to set,

but it is likely that

incipient cultivation

and domestication

developed sometime

around 10,000 B.C. in

the Near East.



(sometimes described as the “world’s oldest town”) housed several hundred people, and they were defi nitely agriculturalists. The rimland around the Fertile Crescent was one of the fi rst areas to experience the agricultural changes that would slowly burgeon into a major revolution. As Weatherford (1994, 111) pointed out, “The transition from rural to urban life fi rst occurred in Mesopotamia with the rise of Uruk, Sumer, and other cit-ies in the area between the Tigris and Euphrates rivers, in modern Iraq.” As agricultural practices evolved and diffused, people experienced tremendous changes; they were able to turn from the wandering and tenuous life of hunter-gatherers to the more sedentary and secure life of agriculturalists. However, these changes were gradual. As Cipolla (1974, 22) noted:

It can be stated however, with a fair degree of certainty that the foundations of settled life in the Old World were fi rst laid in South-West Asia between the ninth and the seventh millennium B.C. This seemingly took place where prototypes of the earliest domesticated animals and plants existed in a wild state and where the concentration on particular species as sources of food was stimulated by the eco-logical changes that marked the transition to Neothermal climate.

Between perhaps 7,000 B.C. and 5,000 B.C. there was some possible domestication of plants in Mesoamerica. Following 5,000 B.C., a slow but consistent domestication contin-ued there (Diamond, 1997).

The introduction of farming allowed greater population densities to exist and proba-bly produced the fi rst food surpluses people had ever known. In turn, a few people were then freed from the fundamental task of providing food. A multitude of inventions and innovations followed, including the development of village settlements, irrigation, metal-lurgy, and long-distance trade. These inventions and innovations in turn increased people’s capacity to satisfy their needs from the environment and further increased the carrying capacity of the land. Trade, and the convergence of trade routes, certainly affected popula-tion distribution and the rise of early cities as well. From today’s perspective it seems clear that agriculture brought with it both risks and rewards. Hunters and gatherers lived in small groups, worked together, and did not have a well-defi ned hierarchical structure. As Weatherford (1994, 50) noted, “The division of the world between farmers and foragers created a permanent tension between two types of subsistence with very different needs.” Clearly, with the shift to agriculture new skills and ways of thinking appeared, and, as McNeill and McNeill (2003, 6) pointed out, “Economic specialization and exchange cre-ated poverty as well as wealth.”

The demographic response to agricultural and related changes was a gradual acceleration in the rate of population growth. As the agricultural revolution diffused to various parts of the earth’s inhabited surface, its impact on population growth became increasingly signifi cant. However, as Deevey’s interpretation suggested, once the impact of this revolutionary increase in the earth’s carrying capacity had completed its diffusion, the

rate of population growth slowed again, and the population became stabilized at a new and higher plateau. Geographic variations in population growth rates existed, however. For example, McNeill and McNeill (2003, 37) noted that “In temperate climates, where diseases were less burdensome than in tropical lands, farming village populations clearly grew much faster than hunting bands had previously done.” At the same time, settled people were more vulnerable to certain risks, including infectious diseases.

By the beginning of the Christian Era the earth’s population was about 250–300 million. Though this population continued to grow, its numerical progress was slow, and the regional distribution of growth was varied. Within the overall pattern of growth, cycli-cal changes were typical. The rate of population growth was kept in check by food supplies (often interrupted by famines), by wars, and by epidemics of various diseases.

The introduction

of farming allowed

greater population

densities to exist and

probably produced

the fi rst food sur-

pluses people had

ever known.

“Economic specialization

and exchange created poverty as

well as wealth.”



For the most part famines have been localized, and their impact on the death rate depends on both the severity of the famine and the links between the famine-stricken area and other locations. However, famines have occasionally been devastating. Fourteenth century China may have experienced the planet’s fi rst great famine (with deaths thought to be in excess of 4 million); they occurred in many regions over the next few centu-ries, including the great potato famines in Ireland (1845–1849). Since 1900 famines have been worst in China (1921–1923 and 1928–1929), India (1943–1944 and 1965), and Russia (1932–1934, 1941–1944, and 1947), though they have occurred also in Poland, Gr eece, Africa’s Sahel region, Ethiopia, Bangladesh, Somalia, Nigeria, and Kampuchea. With improved transportation linkages, the effects of local crop failures have gradually diminished.

Wars have directly affected population growth rates at various times, but their impact is not always easy to assess. The simple counting of battlefi eld deaths alone would underes-timate the demographic impact of most wars, because wars also disrupt food supplies and act as diffusion agents for numerous diseases. Of war and the latter, Zinsser (1967, 113) commented, “And typhus, with its brothers and sisters—plague, cholera, typhoid, dysen-tery—has decided more campaigns than Caesar, Hannibal, Napoleon, and all the inspec-tor generals of history.” The greatest losses occurred in World War I and World War II.

Epidemics and pandemics have often been devastating in their impact on regional populations. Extreme examples include the Justinian Plague of A.D. 541–544 and the Black Death of A.D. 1346–1348. The latter may have reduced the European population by 25 percent, and local death tolls reached as high as 50 percent. Recovery of the European population after this decimation was slow, and it was further hampered by the One Hun-dred Years War. By the sixteenth century, however, Europe had regained her lost popula-tion and was beginning a gradual acceleration in the rate of population growth, though there were still localized periods of famine, war, and disease. The rapid growth and distri-bution of AIDS since the 1980s (discussed in Chapter 4) convinced everyone who might have thought otherwise that epidemics and pandemics are still with us.

After 1492 population declined precipitously in the New World as well. Though we will never know for sure, reasonable estimates suggest that more than 50 million people lived in the Americas when Columbus fi rst sailed westward. As journalist Lewis Lord (1997, 70) noted, “The 150 years after Columbus’s arrival brought a toll on human life in this hemisphere comparable to all of the world’s losses in World War II.” Geographer William Denevan (1996) explored estimates of the Native American population in detail. Diamond (1997, 2005) suggested that 95 percent of the Native American population died as a result of diseases introduced by Europeans into the New World. A more recent study by Livi-Bacci (2006) further supports the idea that new world populations were decimated by contact with early European explorers.

The Industrial RevolutionThe Industrial Revolution originated in England in the latter half of the eighteenth cen-tury, though its roots may be found in earlier times. At its heart, the Industrial Revolution was a shift from animate to inanimate energy sources, from humans and domesticated animals to steam power generated by carbon fuels–charcoal, coal, then later oil and natural gas. Its impact on humans was vast, fairly rapid, and underwent a geographic dispersion that continues to this very day. As McNeill and McNeill (2003, 248) commented, “Indus-trialization forever altered the nature of work. From the natural rhythm of the days and seasons that governed farm work, people shifted to schedules controlled by the clock.” The shift of populations from rural to urban areas began, and the world became noisier, often dirtier, and undoubtedly warmer as well. From England it diffused rapidly into the countries of Western Europe and to the United States. By the beginning of the twentieth century it had reached Russia and Northern Italy. Japan was the fi rst Asian country to



experience this revolution. As countries industrialized, industry replaced agriculture as the major sector of the economy. The Industrial Revolution continues today, and it has so far only partially diffused to the less developed countries. New inventions and innovations continue to pour forth almost daily.

By about 1750 in England and Wales, and soon thereafter in other countries as they began to industrialize, population growth accelerated. Prior to this time, crude birth and death rates had both tended to be high. In average years there may have been more births than deaths, while in bad years the reverse was likely. Death rates undoubtedly fl uctuated more widely than did birth rates. High birth rates were deemed necessary in order to over-come the prevailing high death rates, though birth rates were generally not as high as they might have been because of a variety of social constraints.

During both the cultural and agricultural revolutions people increased their capacity to wrest a living from the earth, but it was not until the scientifi c-industrial revolution that, for the fi rst time, they began to gain control over death. This control over death rates was a result of many changes, mainly changes that probably at fi rst cut off the high peaks in the cyclical fl uctuations of death rates. Better agricultural practices and improved distribution systems cut down on the localized effects of famines. Improved sanitary practices and facilities decreased the deaths from some diseases quite early. Then during the nineteenth century major medical advances accelerated the downward trend in death rates.

The innovations associated with each revolution were not contained in their area of origin but diffused outward, as is well illustrated by the spread of the Neolithic farming cultures of Europe. In 6,000 B.C. farming in Europe was primarily limited to a few sites near the Aegean Sea. During the next 1,000 years it spread northward into the Danubian Basin and by 4,000 B.C. to the North European Plain. An even more rapid diffusion of the industrial-scientifi c revolution has occurred. These innovations were carried by Europeans as they colonized new areas, and in the current century there are few places that have not been touched by industrialization to some degree.

The speed and direction of diffusion was governed by such things as distance, obsta-cles, nature of the environmental base, and receptivity of various social structures. One critical point is that the spread of new innovations was uneven. Whenever such innova-tions were introduced into a society there was a traumatic effect that necessitated new forms of organization, new patterns of leadership, and the acquisition of new skills. Rapid population growth often accompanied the changing socioeconomic conditions.

One further point to be emphasized about Deevey’s (1960) interpretation of world population growth is the nature of the population growth curve for each revolution. After each rapid spurt in population growth, the growth rates slackened off—the numbers reached a plateau, and then further additions were slow to be achieved. Each revolution therefore removed, partially at least, some pre-existing constraint upon population growth, but it must also have set into motion forces that eventually brought growth under control. Obviously, these forces are of urgent concern in our present circumstance.

In response to the Industrial Revolution the world’s population entered a period of rapid and sustained population growth. During the nineteenth century this growth was concentrated in the more developed countries. By the middle of the twentieth century, however, population growth had subsided in the more developed countries and was acceler-ating in the less developed countries, setting the demographic stage for the new millennium.

Many would have predicted that the rapid population growth of the twentieth cen-tury (from about 1.6 billion in 1900 to 6.1 billion in 2000) would have resulted in a world of extreme poverty and economic deprivation as resource scarcities led to higher prices for basic commodities. Such was not the case, however, and we need to keep this in mind as we look ahead to discussions of population growth and economic well-being, food supplies, and environmental concerns. We also need to keep in mind that the near-quadrupling of

The Industrial

Revolution originated

in England in the

latter half of the

eighteenth century,

though its roots may

be found in earlier

times.



the world’s population during the twentieth century was made possible in large part by the widespread development and use of fossil fuels.

Though no defi nitive yardstick is available for measuring such things, economists have suggested that the world’s material standard of living increased perhaps nine-fold during the twentieth century—a considerable achievement. On the average people live longer, healthier lives now than they did 100 years ago. Geographically, however, the va st improvements in wealth during the twentieth century accrued mainly to the nations of Europe, the United States, and Japan. We enter the new century with vast differences in wealth among the world’s nations—a person’s place of birth largely determines his or her economic and demographic destiny.

The Human Population TodayJane Jacobs (2004, 168) noted, perceptively, that “The world today is a bewildering mosaic of cultural winners, groups of people sunk into old or recent Dark Ages and downward spirals, groups in the process of climbing out, and remnants of preagrarian cultures, as well as remnants of declined empires.”

Today’s population situation is unique in the world’s history; not only is the cur-rent rate of increase still fairly high, but the base population (7 billion) is also the largest ever. The historical record shows that the acceleration of world population growth started with the European countries and the lands that Europeans settled overseas, especially the United States, Canada, and Australia. However, the areas that are growing the fastest today are Africa, Asia, and Latin America. These so-called less developed regions have more than three-fourths of humankind and are responsible for more than 90 percent of the world’s population growth. Death rates in these regions’ countries have been falling during the last twenty-fi ve years, whereas birth rates have remained twice as high as they are in the more developed nations (Goldstein and Schlag, 1999).

Between 1950 and 1987 the world’s population doubled from around 2.5 billion to over 5 billion, an increase of over 2.5 billion people in less than forty years. The Cold War ignored growing populations and changing geographic concentrations of people. During those years population growth had been unequally distributed geographically; more than 85 percent of that growth occurred in the less developed countries. In most of the more developed countries today, fertility hovers near or below replacement level (the United States is the major exception), so that an even higher percentage of population growth in coming decades will occur in the less developed countries, those least able to absorb additional people. By the year 2008, 85.4 percent of the world’s population resided in the less developed countries; nearly half of them were residents of either China or India (the world’s second “demographic billionaire”). It is easy to see why, then, we can expect inter-national migration to fl ourish in the decades ahead as globalization of the economy brings together capital, which is heavily concentrated in the rich countries, and young people, who are heavily concentrated in the poor ones.

Still another comparison between the more developed and less developed countries can be made by considering the differing age structures of their populations. A country that has a rapidly growing population has a large proportion of its residents in the younger age groups. In the rapidly growing areas of the world—Africa, Asia, and Latin America—high proportions (typically 30–45 percent) of the population are under 15 years of age, whereas in North America, Europe, and Australia and New Zealand there are signifi cantly lower proportions of young people (20 percent or less). A population with a large propor-tion of old people will have different needs and requirements than a population with a great many young people. Though we don’t know exactly what the earth’s carrying capac-ity for humans actually is today, many would argue that we may be approaching it soon. Some would even suggest that we’ve already passed it.

A person’s place of

birth largely deter-

mines his or her

economic and demo-

graphic destiny.



However, overpopulation is an elusive concept. Though it may seem to you that parts of the world are indeed overpopulated, that doesn’t mean either that everyone would agree with you or that, by virtue of some regions being overpopulated, that the world is also overpopulated. If we could defi ne an optimum population, then it would be easier to defi ne overpopulation. It would be any population greater than the optimum. But there is no agreed upon defi nition of optimum population. Optimum for whom, we might ask, and for what? We might try to relate the optimum population in turn to carrying capacity, but as we’ve seen already, the carrying capacity of the world has been regularly altered by changes in technology that have allowed us to produce more food, the essential need that we humans have. We will revisit these ideas in more detail in Chapter 9, though we will never resolve the issue to everyone’s satisfaction.

Population ProjectionsSo far we have viewed the present population situation mainly in the perspective of the past, but what does the future hold in store for the world’s population? One answer to that question, based on a set of assumptions about the dynamics of a population over some time period, is the population projection. Young (1968, ix) cautioned us long ago, however, to remember that:

The projection of a future population from a present growth rate is a hazardous undertaking at best. These rates contain many variables and are sensitive to small changes in these variables. Furthermore, since population growth is cumulative, very slight changes in present rates can make enormous differences when pro-jected 100, 200, or more years into the future.

Always remember that we cannot predict the future, and those who try are doomed to failure. As only one example, in 1949 Popular Mechanics predicted that “Computers in the future may weigh no more than 1.5 tons.”

Demographers are careful to differentiate between projections and predictions. The projection for the size of a population at some future date is based on a set of assumptions about the demographic processes that will affect population growth over the time period. The simplest assumption is that the future rate of population growth will be the same as that of today. However, for most situations this is unrealistic. Typically, the projection is broken down into separate projections for the birth rate, death rate, and migration. These may then be combined into a single projection for the future population. What the projec-tion shows is that, if the assumptions hold true for births, deaths, and migration, then the projection will be accurate. Demographers should not be held responsible if the assump-tions are not fulfi lled, you see. Often a projection may alter people’s reproductive behavior and set into motion events that will assure that the projection will be off the mark. Usually more than one projection is made and quite often a series of projections is made, using different assumptions about future birth, death, and migration rates.

Population Projections: A Brief OverviewFirst, we should distinguish among the following three commonly encountered terms: projection, forecast, and prediction. A population projection is made on the basis of the population at some date and assumptions about births, deaths, and migration between that date and some future date. As Gibson (1977, 7) noted, “Population projections are ‘correct’ by defi nition (except for computational errors) because they indicate the popula-tion that would result if the base data (starting) population is correct and if the underlying assumptions about future change should turn out to be correct.” The usefulness of projec-tions, then, depends on what assumptions have been made and how well they accord with the actual events.

A population projection is made on the basis of the

population at some

date and assumptions

about births, deaths, and

migration between that

date and some future

date.



Demographers prefer to avoid the term prediction altogether because it suggests that only one projection has been made and it is considered as an ultimate truth, as occurring wi th a high degree of certainty. Past projections have often fallen so wide from their marks that the most demographers will venture today is to choose one of a series of projections as a forecast, and that usually only for short distances into the future, and then only reluctantly.

Two broad classes of population projections exist: mathematical and component. Mathematical methods are easier to understand and to apply, but component methods are preferable for most projections, especially for those beyond the short term, which is usually taken to be fi ve years or less. Whereas mathematical methods employ some math-ematical formula to a base population using an assumed rate of growth over the projection interval, component models separately project births, deaths, and migration, then com-bine the “components” into an overall population projection. These latter projections, of course, are also done mathematically, and the terminology sometimes confuses people. For demographers and population geographers there is no escape from mathematics.

Within each class of projections different models exist, so a wide range of projection models can be called upon. The model that should be used, of course, depends upon sev-eral factors, such as the size of the area for which projections are being made, the assump-tions that can or should be made, the types of data that are available, and the length of the projection interval. With respect to scale, for example, national projections require different considerations than do projections for local areas. Understanding and project-ing migration is, perhaps, more critical for local area projections than is the projecting of births and deaths. Conversely, projecting immigration at the national level may be much easier than projecting births mainly because immigration is controlled, at least to some extent, by the national government. Also, data for local areas are not always available in suffi cient detail for employing component models, thus making mathematical models more attractive, especially for short-term projections.

Population Projections: World and Major RegionsDespite the diffi culties, population projections are deemed essential and useful. They can stimulate our thinking about the consequences of population trends, for example. We need to keep in mind, however, what a United Nations study stated:

What will population trends be like beyond 2050? No one really knows. Any demographic projections, if they go 100, 200, or 300 years into the future, are little more than guesses. Societies change considerably over hundreds of years—as one can readily see if one looks back at where the world was in 1900, or 1800, or 1700. Demographic behavior over such long time spans, like behavior in many spheres of life, is largely unpredictable (United Nations, 2004, 3).

The United Nations’ world and regional population projections for the 1950–2050 period are shown in Table 1–1. Among the basic assumptions that the United Nations used to make these projections are the following:

1. At least a minimal degree of social order and control will be maintained. 2. Efforts at maintaining or improving the quality of life will continue and will not be

totally frustrated. 3. Regional vital rates will move differently in terms of time, but eventually everywhere

mortality and fertility will fall slightly below the lowest levels now observed.

As Table 1–1 shows, the potential for population growth is considerably higher in the less developed areas of the world than in the more developed ones.

Mathematical meth-ods employ some

mathematical formula

to a base population

using an assumed rate

of growth over the

projection interval.

Component mod-els separately project

births, deaths, and

migration, then combine

the “components” into

an overall population

projection.



After getting close to 7 billion in 2010, the world’s population is projected to increase by nearly 30 percent over the next 50 years, to a population of slightly over 9 billion according to the medium variant of the United Nation’s updated projections. Generally, the future course of fertility is more diffi cult to project than that for mortality.

Population Projections: The United StatesFor comparative purposes it is useful to look at what has happened to offi cial population projections for the United States. These projections are extremely important because they serve as the basis for many other projections, including the country’s projections of the demand for housing, educational facilities, hospitals, and a myriad of other needs.

Population projections for the United States in the 2000–2100 period are shown in Table 1–2. Though these projections were published in early 2000, they do not include the 2000 census fi gures, which showed a population about 6 million larger than the 2000 fi gure used for projections. As a result, these projections are assuredly on the low side. The assumptions underlying the different variants in Table 1–2 are discussed in Hollmann, Mulder, and Kallan (2000). The middle series is considered the “most likely” variant, though with the usual caveat. In a commentary in Time magazine, Stengel (2006) wrote about the growing population of the United States as it passed the 300 million mark. He went on to celebrate the nation’s growth and pointed out that it would only take about 40 more years to reach 400 million. He wrote that (2006, 8) “In America, we have always done Big well–big cars, big screens, Big Macs; we’re the supersize nation. But now we are being challenged to trade Big for Smart.” He didn’t even mention the possibility of trad-ing Big for Smaller. Even if we were to build “greener” buildings, squeeze more miles per gallon out of cars, and put solar panels on Wal-Marts, another 100 million Americans will further burden Earth’s environment.

Given discussions in the United States about immigration rates, it is of particular interest to note the fi nal column of the projections in Table 1–2 because they assume no

Table 1–1 Population of the World, Major Development Groups and Major Areas, 1950, 1975, 2010 and 2050

According to Different Variants

Major area

Population (millions) Population in 2050 (millions)

1950 1975 2010 Low Medium High Constant

World 2 535 4 076 6 895 8 112 9 306 10 614 10 943

More developed regions 814 1 048 1 235 1 158 1 311 1 478 1 252

Less developed regions 1 722 3 028 5 659 6 955 7 994 9 136 9 691

Least developed countries 200 358 832 1 517 1 726 1 952 2 434

Other less developed countries 1 521 2 670 4 827 5 437 6 267 7 184 7 257

Africa 224 416 1 022 1 932 2 191 2 470 2 997

Asia 1 411 2 394 4 164 4 458 5 142 5 898 5 908

Europe 548 676 738 632 719 814 672

Latin America and the Caribbean 168 325 590 646 751 869 863

Northern America 172 243 344 396 447 501 444

Oceania 13 21 36 49 55 62 60

Source: Population Division of the Department of Economic and Social Affairs of the United Nations Secretariat (2011). World Popula-

tion Prospects: The 2010 Revision. Highlights. New York: United Nations.



immigration. As a result, we see that the difference between the middle series variant and the zero immigration variant is about 76 million people by 2050 and more than 193 mil-lion by 2100. No matter how we view it, the United States will have a much larger popu-lation in the future if current high rates of immigration are sustained, which seems likely. Tables 1–3 and 1–4 show how different age and race groups will be affected by population change.

In summary, selecting an appropriate growth rate for projecting a population requires numerous considerations. We must look not only at past trends and current patterns, but also try to look at ways in which these trends may be altered in the future. Our projections can be no better than the assumptions upon which they are based. In addition, studying projections forces us to confront different scenarios about the consequences of different growth patterns and the possibility of designing policies to affect those patterns (Lee, 2000).

Small Area Population ProjectionsThough national population projections are of considerable importance, they are not the only ones that are of interest. Political units, from states to counties and cities, need to know something about their demographic futures, as do local school districts, highway

Table 1–2 Population Projections for the United States

Middle Series Lowest Series Highest SeriesZero International Migration Series

2000 275,306 274,853 275,816 273,818

2005 287,716 284,000 292,339 280,859

2010 299,862 291,413 310,910 287,710

2015 312,268 297,977 331,636 294,741

2020 324,927 303,664 354,642 301,636

2025 337,815 308,229 380,397 307,923

2030 351,070 311,656 409,604 313,219

2035 364,319 313,819 441,618 317,534

2040 377,350 314,673 475,949 321,167

2045 390,398 314,484 512,904 324,449

2050 403,687 313,546 552,757 327,641

2055 417,478 312,160 595,885 330,991

2060 432,011 310,533 642,752 334,724

2065 447,416 308,716 693,790 338,999

2070 463,639 306,589 749,257 343,815

2075 480,504 303,970 809,243 349,032

2080 497,830 300,747 873,794 354,471

2085 515,529 296,923 943,062 360,026

2090 533,605 292,584 1,017,344 365,689

2095 552,086 287,826 1,097,007 371,492

2100 570,954 282,706 1,182,390 377,444

Source: U.S. Census Bureau. www.census.gov/population/projections/nation/summary/np-t1.pdf.

(Feb. 14, 2000)



Table 1–3 Projected Population of the United States, by Age and Sex: 2000 to 2050 (In thousands except as

indicated. As of July 1. Resident population.)

Population or percent, sex, and age 2000 2010 2020 2030 2040 2050

Population Total

Total 282,125 308,936 335,805 363,584 391,946 419,854

0–4 19,218 21,426 22,932 24,272 26,299 28,080

5–19 61,331 61,810 65,955 70,832 75,326 81,067

20–44 104,075 104,444 108,632 114,747 121,659 130,897

45–64 62,440 81,012 83,653 82,280 88,611 93,104

65–84 30,794 34,120 47,363 61,850 64,640 65,844

85+ 4,267 6,123 7,269 9,603 15,409 20,861

Male

Total 138,411 151,815 165,093 178,563 192,405 206,477

0–4 9,831 10,947 11,716 12,399 13,437 14,348

5–19 31,454 31,622 33,704 36,199 38,496 41,435

20–44 52,294 52,732 54,966 58,000 61,450 66,152

45–64 30,381 39,502 40,966 40,622 43,961 46,214

65–84 13,212 15,069 21,337 28,003 29,488 30,579

85+ 1,240 1,942 2,403 3,340 5,573 7,749

Female

Total 143,713 157,121 170,711 185,022 199,540 213,377

0–4 9,387 10,479 11,216 11,873 12,863 13,732

5–19 29,877 30,187 32,251 34,633 36,831 39,632

20–44 51,781 51,711 53,666 56,747 60,209 64,745

45–64 32,059 41,510 42,687 41,658 44,650 46,891

65–84 17,582 19,051 26,026 33,848 35,152 35,265

85+ 3,028 4,182 4,866 6,263 9,836 13,112

Percent of Total

Total

Total 100.0 100.0 100.0 100.0 100.0 100.0

0–4 6.8 6.9 6.8 6.7 6.7 6.7

5–19 21.7 20.0 19.6 19.5 19.2 19.3

20–44 36.9 33.8 32.3 31.6 31.0 31.2

45–64 22.1 26.2 24.9 22.6 22.6 22.2

65–84 10.9 11.0 14.1 17.0 16.5 15.7

85+ 1.5 2.0 2.2 2.6 3.9 5.0



Table 1–4 Projected Population of the United States, by Race and Hispanic Origin: 2000 to 2050 (In thousands

except as indicated. As of July 1. Resident population.)

Population or percent and race or Hispanic origin 2000 2010 2020 2030 2040 2050

Population Total 282,125 308,936 335,805 363,584 391,946 419,854

White alone 228,548 244,995 260,629 275,731 289,690 302,626

Black alone 35,818 40,454 45,365 50,442 55,876 61,361

Asian alone 10,684 14,241 17,988 22,580 27,992 33,430

All other races 1/ 7,075 9,246 11,822 14,831 18,388 22,437

Hispanic (of any race) 35,622 47,756 59,756 73,055 87,585 102,560

White alone, not 195,729 201,112 205,936 209,176 210,331 210,283Hispanic

Percent of Total

Population Total 100.0 100.0 100.0 100.0 100.0 100.0

White alone 81.0 79.3 77.6 75.8 73.9 72.1

Black alone 12.7 13.1 13.5 13.9 14.3 14.6

Asian Alone 3.8 4.6 5.4 6.2 7.1 8.0

All other races 1/ 2.5 3.0 3.5 4.1 4.7 5.3

Hispanic (of any race) 12.6 15.5 17.8 20.1 22.3 24.4

White alone, not 69.4 65.1 61.3 57.5 53.7 50.1Hispanic

1/ Includes American Indian and Alaska native alone, native Hawaiian and other Pacifi c islander alone, and two or more races.

Source: U.S. Census Bureau, 2004, “U.S. Interim Projections by Age, Sex, Race, and Hispanic Origin,” <http://www.census.gov/ipc/www/

usinterimproj/> Internet Release Date: March 18, 2004.

Male

Total 100.0 100.0 100.0 100.0 100.0 100.0

0–4 7.1 7.2 7.1 6.9 7.0 6.9

5–19 22.7 20.8 20.4 20.3 20.0 20.1

20–44 37.8 34.7 33.3 32.5 31.9 32.0

45–64 21.9 26.0 24.8 22.7 22.8 22.4

65–84 9.5 9.9 12.9 15.7 15.3 14.8

85+ 0.9 1.3 1.5 1.9 2.9 3.8

Female

Total 100.0 100.0 100.0 100.0 100.0 100.0

0–4 6.5 6.7 6.6 6.4 6.4 6.4

5–19 20.8 19.2 18.9 18.7 18.5 18.6

20–44 36.0 32.9 31.4 30.7 30.2 30.3

45–64 22.3 26.4 25.0 22.5 22.4 22.0

65–84 12.2 12.1 15.2 18.3 17.6 16.5

85+ 2.1 2.7 2.9 3.4 4.9 6.1

Source: U.S. Census Bureau, 2004, “U.S. Interim Projections by Age, Sex, Race, and Hispanic Origin,” <http://www.census.gov/ipc/www/

usinterimproj/>Internet Release Date: March 18, 2004.



planners, and urban and regional planning departments. In addition, numerous private corporations are interested in the changing demographics of local areas, so that they can better gauge local and regional changes in demand, marketing strategies, and even chang-ing tastes and preferences. Thus the need for small area, that is, subnational, population projections exists and is growing.

At the same time, as you might expect, small area population projections are more dif-fi cult to make because local variations in fertility, mortality, and migration may be much wider than those at the national scale. Especially diffi cult to project are migration rates for local areas, because changes in an area’s socioeconomic characteristics may quickly alter current migration patterns. For example, no one looking at the changes that had occurred in the Asian population in Long Beach, California, during the 1970s would have projected that that city and neighboring Lakewood would have a population of more than 20,000 Cambodians by 2000. At best, small area projections are a tricky business, and changing migration patterns are the major culprit.

The United States Bureau of the Census often publishes state population projections (Table 1–5 is one example). But even there the assumptions that must be made are diffi cult to choose. Consequently, different projections result primarily from different assumptions about migration patterns. However, the Bureau wisely chooses not to do population pro-jections for areas smaller than states, leaving that task to state and local agencies and to private fi rms such as Donnelley Marketing Information Systems.

Culture, Population Growth, and PlanningThe United Nations designated 1974 as World Population Year and in August of that year convened the World Population Conference in Bucharest, Romania. The purpose of that conference was to focus world attention on problems associated with population growth. At the time it was the largest international population meeting ever held and had repre-sentatives from 136 governments around the world.

Though most governments recognized the existence of population problems in their own countries, as well as throughout the world, there was much disagreement and debate about the reasons for the problems and the types of solutions that should be implemented. A number of countries participating in the conference felt that the reason for high birth rates was the lack of social and economic development, so that the emphasis should not be put on population and family planning programs but rather on development. One of the frequently heard slogans at Bucharest was “Take care of the people, and the popula-tion will take care of itself.” A different position, however, was taken by a number of other countries, including the Western European nations, the United States, and Canada, which felt that reductions in population growth rates would make a substantial contribution to the process of economic development and that what was needed fi rst was a decrease in population growth to induce development.

A more lucid explanation of this relationship between population-family planning and development was expressed by Nortman and Hoffstater (1975, 3):

Whatever the stance on the political stage, the most ardent family planning advo-cates recognize that contraception “alone” will not produce housing, schools, or steel mills; and among the staunchest supporters of the “new economic order,” many appreciate the demographic value of legitimated and government-subsi-dized family planning services.

At least three different positions on the population problem can be identifi ed. One position is that population growth is a crisis issue and the problem is so grave that catas-trophe is near unless dramatic actions are followed in order to reduce the growth. A second position is held by those who feel that population growth will intensify and multiply other

Small area popula-

tion projections are

more diffi cult to

make because local

variations in fertility,

mortality, and migra-

tion may be much

wider than those at

the national scale.


Tabl

e 1–

5 Popula

tion P

roje

ctio

ns

for

Colo

rado, 2

000–2020

Age

Gro

up

Cen

sus

2000

Pro

ject

ion

2020

2000

–202

0 C

hang

e

Num

ber

Perc

ent

Num

ber

Perc

ent

Tota

l

Tota

lM

ale

Fem

ale

Tota

lTo

tal

Mal

eFe

mal

eTo

tal

Num

ber

Perc

ent

Tota

l4,

301,

261

2,16

5,98

32,

135,

278

100.

05,

278,

867

2,67

3,75

22,

605,

115

100.

097

7,60

622

.7

0–4

297,

505

152,

353

145,

152

6.9

387,

617

198,

926

188,

691

7.3

90,1

1230

.3

5–9

308,

428

158,

119

150,

309

7.2

374,

214

192,

310

181,

904

7.1

65,7

8621

.3

10–1

431

1,49

716

0,11

815

1,37

97.

235

4,82

918

2,24

617

2,58

36.

743

,332

13.9

15–1

930

7,23

815

9,97

114

7,26

77.

135

6,20

618

5,67

317

0,53

36.

748

,968

15.9

20–2

430

6,23

816

2,61

914

3,61

97.

134

8,67

118

3,26

016

5,41

16.

642

,433

13.9

25–2

933

1,79

517

5,59

315

6,20

27.

736

6,05

419

1,20

817

4,84

66.

934

,259

10.3

30–3

433

2,23

217

2,89

815

9,33

47.

737

5,79

819

5,90

617

9,89

27.

143

,566

13.1

35–3

936

6,09

218

5,71

218

0,38

08.

536

2,53

318

7,56

117

4,97

26.

9-3

,559

-1.0

40–4

437

0,73

118

6,63

418

4,09

78.

633

7,21

717

5,41

416

1,80

36.

4-3

3,51

4-9

.0

45–4

933

4,85

516

7,89

916

6,95

67.

833

2,14

517

2,59

715

9,54

86.

3-2

,710

-0.8

50–5

427

9,27

014

0,45

213

8,81

86.

531

4,50

516

1,69

715

2,80

86.

035

,235

12.6

55–5

919

4,72

296

,345

98,3

774.

531

7,17

816

0,41

815

6,76

06.

012

2,45

662

.9

60–6

414

4,58

570

,739

73,8

463.

430

0,99

714

9,73

215

1,26

55.

715

6,41

210

8.2

65–6

912

1,22

257

,663

63,5

592.

825

3,42

712

3,14

313

0,28

44.

813

2,20

510

9.1

70–7

410

5,08

847

,250

57,8

382.

419

7,01

193

,439

103,

572

3.7

91,9

2387

.5

75–7

985

,922

36,0

4349

,879

2.0

124,

550

55,1

2869

,422

2.4

38,6

2845

.0

80–8

455

,625

21,4

2234

,203

1.3

81,1

4133

,357

47,7

841.

525

,516

45.9

85+

48,2

1614

,153

34,0

631.

194

,774

31,7

3763

,037

1.8

46,5

5896

.6

Und

er 1

81,

100,

795

565,

710

535,

085

25.6

1,32

7,46

768

2,91

264

4,55

525

.122

6,67

220

.6

5–17

803,

290

413,

357

389,

933

18.7

939,

850

483,

986

455,

864

17.8

136,

560

17.0

18–2

443

0,11

122

7,47

020

2,64

110

.049

4,07

025

9,50

323

4,56

79.

463

,959

14.9

25–4

41,

400,

850

720,

837

680,

013

32.6

1,44

1,60

275

0,08

969

1,51

327

.340

,752

2.9

45–6

495

3,43

247

5,43

547

7,99

722

.21,

264,

825

644,

444

620,

381

24.0

311,

393

32.7

65+

416,

073

176,

531

239,

542

9.7

750,

903

336,

804

414,

099

14.2

334,

830

80.5

(Con

tinue

d )

23


Dem

ogra

phic

Ind

icat

or20

0020

20C

hang

eD

emog

raph

ic I

ndic

ator

2000

2020

Cha

nge

Med

ian

Age

34.3

36.0

1.7

Chi

ld-W

oman

Rat

io (

4)30

.637

.77.

1

Mal

e33

.235

.22.

0Se

x R

atio

(5)

101.

410

2.6

1.2

Fem

ale

35.4

36.9

1.5

Und

er 1

810

5.7

106.

00.

2

Dep

ende

ncy

Rat

io (

1)61

.772

.811

.118

–64

104.

610

7.0

2.3

Yout

h (2

)46

.048

.22.

265

–84

79.0

86.9

7.9

Old

Age

(3)

15.6

24.6

8.9

85+

41.5

50.3

8.8

(1)

Dependency

Rat

io �

(A

ge u

nder

20 �

Age

65 a

nd o

ver)

/ (

Age

20–64)

� 1

00

(2) Y

outh

dependency

rat

io �

Age

under

20 /

Age

20–64 �

100

(3)

Old

age

dependency

rat

io �

Age

65 a

nd o

ver

/ Age

20–64 �

100

(4)

Child

-Wom

en r

atio

� A

ge u

nder

5 /

Fem

ale 1

5–44 �

100

(5)

Sex R

atio

� M

ale /

Fem

ale �

100

Sour

ce: U

.S. C

ensu

s B

ure

au, P

opula

tion D

ivis

ion, I

nte

rim

Sta

te P

opula

tion P

roje

ctio

ns, 2

005 Inte

rnet

Rele

ase D

ate: A

pri

l 21, 2

005

24



social problems, but that although population is important, it is not everything. A third position is held by those who feel that population is a nonproblem, or even a false prob-lem, with the real problem being development or redistribution of income and power. A small but growing concern among demographers and others is with population decline, which has already begun in many European nations and a few others as well. An unex-pected consequence of modernization has been the decline of birth rates to below replace-ment level. In summary, the very nature of the population problem and the consequences of population growth are under closer scrutiny and examination today than at any time in the past (Hardin, 1999).

The Laissez-Faire Point of ViewThe general argument stated by those in favor of some form of population control is that individual fertility decisions do not add up to what is socially optimal, or even desirable, hence such decisions cannot be left to individual families. Thus, parents intending to have children may impose a signifi cant part of the cost and responsibility for those children on people other than themselves. These parents are therefore likely to have “too many” children.

On the other hand, however, there are those in favor of a laissez-faire solution. They feel that it is a question of individual choice, because it is the individual who bears the cost and receives the benefi ts of his own action. In general, the laissez-faire argument regard-ing population control is essentially the same as the laissez-faire argument in economics. Under proper functioning of the free market, without controls, the prices, both monetary and nonmonetary, that people pay for things refl ect the real cost of production; and the prices that they receive refl ect the real value of what they produce. Thus, when an indi-vidual makes an economic decision he or she bears all the costs and receives all the benefi ts. If the costs are less than the benefi ts, a positive decision is made; if the costs are greater than the benefi ts, a negative decision is made.

Laissez-faire population exponents feel that those best able to determine the costs and benefi ts of children are those who are contemplating having them. They are the ones who must assume the fi nancial and social responsibility for that child and they are the ones who will benefi t from that child. There are some, however, who believe that the costs and benefi ts for the family are not the same as the costs and benefi ts derived by the society for each additional child. For the individual family the ideal number of children may be fi ve or six, whereas the ideal family size for the society may be only two.

The Question of Cultural GenocideSomewhat akin to the laissez-faire population exponents are those who feel that popula-tion control is a device proposed by more economically developed countries to control the less economically developed countries. Since the former group of countries is primarily the white non-poor nations and the latter group is the non-white poor nations, many believe that population control is a form of “genocide.”

“Genocide” is a controversial concept with manifold emotional overtones. The United Nations Genocide Convention defi ned genocide as any of the following acts committed with intent to destroy, in whole, or in part, a national, ethnic, racial, or religious group:

• killing members of the group; • causing serious bodily or mental harm to members of the group; • deliberately infl icting on the group conditions to bring about its physical destruction

in whole or in part; • imposing measures intended to prevent births within the group; • forcibly transferring children of the group to another group.

Laissez-faire popula-

tion exponents feel

that those best able

to determine the

costs and benefi ts of

children are those

who are contemplat-

ing having them.

Genocide is the delib-

erate and systematic

destruction of an ethnic,

racial, religious, or

national group.



The above defi nition was adopted unanimously by the General Assembly of the United Nations. According to the defi nition, mass sterilization of a compulsory nature would be considered genocide. Item (D) of the defi nition, “imposing measures intended to prevent births within the group,” is either directly or indirectly related to the family planning programs espoused by the United States and other more developed countries. The impor-tant question thus becomes: Do family planning programs, as espoused by predominantly white, wealthy nations represent conscious, deliberate efforts to curtail nonwhite fertility, or do they refl ect a genuine concern for the well-being and health of the rest of the world?

In an analysis of population control Darden concluded that, in his opinion:

The poor and nonwhite should oppose any program which involves institutional limitation of population growth. Why? Because there is no guarantee that rela-tive poverty would decline if the poor and nonwhites accepted such a fertility program. There might be fewer poor people in absolute numbers, but the gap between rich and poor would either get wider or remain constant. . . . In brief, institutionalized, coercive limitation of population growth is a policy aimed directly or indirectly at the poor and nonwhite and is therefore unacceptable as a solution to the problems of hunger, and other social ills in the United States and the world (Darden, 1975, 51).

Genocide is not just a thing of the past, no matter how much human rights are tram-pled in its path. In 2004 the United States offi cially recognized genocide in the Darfur region of the Sudan, even as it did little to stop it. Though humanitarian aid was sent to the region, the killing continues. We are constantly reminded of “man’s inhumanity to man.”

The Ethics of Population ControlAs previously mentioned, there are those who believe that any form of coercive population control is unethical. However, a signifi cant number of people feel that in order to solve the population problem and limit population growth it will be necessary to induce people to limit the size of their families. They feel that the hazards of excessive population growth pose such critical dangers to the future of the species, the ecosystem, individual liberty and welfare, and the structure of social life, that there must be a reexamination and ultimately a revision of the traditional value assigned to unlimited procreation and to the increase in population size.

Callahan (1971, 2) outlined some general ethical guidelines for governmental action and presented them in a “rank order of preferences” from the most preferable to the least preferable. They are listed here and are still very much worth thinking about. The govern-ment has an obligation to do everything in its power to protect, enhance, and implement freedom of choice in family planning. This means the fi rst requirement is to establish effective voluntary family planning programs.

If it turns out that voluntary family planning programs do not curb excessive popula-tion growth, then the government has the right to go “beyond family planning.” Callahan felt, however, that before governments take this second step they must justify the introduc-tion of these new programs by showing that voluntary methods have been adequately and fairly tried. Callahan believed that the voluntary programs had not yet failed because they had not been tried in any massive and systematic way.

When the government has to choose among possible programs which go “beyond family planning,” it has an obligation to fi rst try those programs which, comparatively, are the least coercive. In other words, positive incentive programs and manipulation of social structures should be resorted to before “negative” incentive programs and involuntary fertility controls are applied. According to Callahan, if it appears that some degree of coer-cion is required, that policy or program should be chosen which:



• entails the least amount of coercion; • limits the coercion to the fewest possible cases; • is not problem-specifi c; • allows the most room for dissent of conscience; • limits the coercion to the narrowest possible range of human rights; • least threatens human dignity; • least establishes precedents for other forms of coercion; • is most quickly reversible if conditions change.

In summary, the ethical considerations associated with population control are complex. Population policies, though they must take into account the interests and needs of particu-lar regions and population groups, should have as their ultimate aim the best interests of the entire human species. Any plan to reduce world population growth to (some would argue even below) zero will have to carefully consider at least the following: economic develop-ment (including variations on the “Western model”) and its role in reducing family size, the empowerment of women and gender equity, and the extension of family planning services to provide safe and effi cient means of preventing unwanted births.

Population Dynamics and the World of BusinessDemographic considerations and their spatial or geographic components play an impor-tant role in today’s business world. Understanding these issues is of vital importance to business executives, who are increasingly turning to demographic experts for answers to a variety of problems. As one writer noted, business executives need to “. . . understand population changes and their impact on basic corporate decisions such as labor supply, location of facilities, the changing nature of markets, and the age makeup of consumer groups” (Hyatt, 1979, 1). American Demographics a now discontinued magazine presented succinct looks at the relationship between demographic trends and everything from where to market products to where to retire. Some of the material from American Demographics has since been incorporated into another publication called Advertising Age.

MarketingMarketing relies heavily on demographic statistics and their spatial or geographic aspects. Market segmentation and differentiation now play a key role in marketing strategies. According to Francese and Renaghan (1991, 50), “. . . many markets have become too complicated and too unforgiving to rely on just one or two demographic variables.” A variety of variables such as race, ethnicity, income, education, and age, have a symbiotic relationship and together form the basis of “database marketing.” In order for marketers to succeed in the future they will have to understand the multi-dimensional demographic profi les of their market segment; in the United States multiculturalism itself is becoming a concern for marketing specialists, with growing Latino and Asian populations appealing to many product manufacturers and distributors. Additionally, the aging baby boom is a market segment that will be important in marketing.

The formation of households is an important variable to consider by planners for such utilities as gas, electric, and telephone; population gains and losses certainly shape the demand for power. Changing fertility rates and divorce rates, as well as the increase in the number of late marriages, have a tremendous impact on household formation and thus are important variables when predicting consumer demand for utilities.

African American buying power is expected to reach 1.1 trillion dollars by 2015. Latino buying power was 1 trillion dollars and Asian buying power was 540 billion dol-lars in 2010 (Humphreys, 2010). The gay market is by and large an affl uent one. Average annual income for a gay household was $61,000 compared to $51,914 for the general US



population. Gay buying power in the US was projected in 2010 to be 743 billion dol-lars (Witeck-Combs et al., 2010). Women infl uence 85% of all consumer purchases and account for 7 trillion dollars in spending. African immigrants are estimated to have 50 bil-lion dollars in buying power (New American Dimensions, 2009). Race and ethnic groups as well as many gay communities reside in geographically distinct regions and locations of the US. This fact has obvious implications for the importance of the geographical analysis of markets.

Business ForecastingBusiness people are always interested in the future. They are concerned about next week’s sales, next year’s profi ts, future changes in interest rates, and fi ve-year capital investment schemes. Their natural tendency, however, has been to focus on the next fi scal quarter, instead of the next quarter-century. Short-term symptoms always seem to overshadow long-run causes. Worries about short-term problems tend to obscure the longer run, but, equally important, they obscure changes in population variables. For example, a home builder is usually concerned with changes in interest rates, but a shift in the divorce rate or a shift in migration patterns could be equally as important to that industry. Builders have only recently begun to appreciate the impact of the “Baby Boom,” and the boomers have yet to have their impact on Medicare and Social Security, though it is now beginning.

The impact of population change on business forecasting has recently taken on added importance. In a study on changing demographics and the future of business, James Hyatt observed that “. . . while only a few years ago the attention was on worldwide population growth rates, analysts are beginning to understand that for the United States a much more complex set of population shifts are at work. Fast, slow, and no growth are all occurring at the same time in different parts of the country” (Hyatt, 1979, 5). This important geo-graphic dimension of population change is now receiving more attention from business forecasters.

Many of the present and future problems and opportunities to be faced by busi-ness have their roots in the most striking demographic phenomena of twentieth-century America: the unique high fertility period that followed the Second World War, the so-called “baby boom.” During the baby boom period, between 1946 and 1964, there were nearly 80 million births in the United States, 50 percent more than during the preceding fi fteen years. The baby boom or “bulge” has far-reaching effects in housing, employ-ment, retail sales, education, and many other areas of concern to the business commu-nity. According to Hyatt (1979, 5), “Business managers would be well advised to keep in mind the location of that bulge from year to year, just as they pay attention to other economic indicators.”

The fi rst baby boomers began to turn 60 in 2006, and as Waldrop (1991, 24) suggested earlier, “It will begin a population explosion among affl uent, maturing householders. And it will turn the 1990s into peak years for consumer spending.” These baby boomers enter-ing midlife brought about changes in a variety of business services. For example, the 1990s saw a rise in consumer demand for bifocal eyeglasses as those midlife boomers underwent inevitable changes due to the aging process. Visual and hearing impairments increase sig-nifi cantly after age forty-fi ve. Increasing attention was paid to health concerns and boom-ers, in order to stay fi t, had to be more selective about food choices. Talk of ice cream and Twinkies gradually gave way to conversations about cholesterol, monounsaturated fats, and triglycerides. This brought about a rise in consumption of food items like fi sh, poul-try, low-fat milk, whole grain cereals and fresh fruits and vegetables. The boomers are also relatively affl uent, and in recent years they have been pouring money into mutual funds and other investments, a major factor in the strong stock market performance during the 1990s, despite an economy that was struggling for the most part.

During the baby

boom period,

between 1946 and

1964, there were

nearly 80 million

births in the United

States, 50 percent

more than during

the preceding fi fteen

years.

Baby boom is the

period following World

War II from 1946−1964

characterized by a rapid

increase in fertility rates

and in the absolute

number of births in the

U.S., Canada, Australia,

and New Zealand.



Although much of the attention of the business community has been focused on the young, there has been an increasing awareness of the aged and the aging of America (Soldo and Agree, 1988). Indeed, adults over age 65 now outnumber teenagers and have become one of the fastest-growing population groups in the country. In 1900 only 3.1 million people in the United States were 65 years of age and older, but by 1985 that fi gure reached 28.5 million and projections for the year 2030 are that there will be 64.6 million. In 1985, one in nine Americans or 11.7 percent of the population was at least 65 years old, but by 2010, because of the maturation of the baby boomers, one in seven Americans will be at least 65 years old (Hooyman and Kiyak, 1988, 22).

As baby boomers become “senior” boomers, “. . . public policy questions how we will support the needs of a growing older population and how we will structure poli-cies to assure a fair and equitable distribution of resources for all age groups” will have to be assured (Bouvier and DeVita, 1991, 27). Government bureaucracies, charged with planning the provision of services for the elderly, will be faced with a variety of decisions with both political and social consequences (Laws, 1991, 32). Some of these problems will be further complicated by the changing ethnic and racial composition of the United States.

Not only will there be more older Americans, but because of their relatively high dis-posable incomes, they will present a growing market for the business community. England (1987, 8) points out that “Americans over age 65 are the second-richest age group in U.S. society. Only those Americans in the next-oldest age bracket, from 55 to 64, are better off.” The aged have assets nearly twice that of the median for the nation. “The spending power of the mature market may be one of the best-kept secrets left in the age of demo-graphic scrutiny,” suggests Lazer (1985, 23).

Zero Population Growth and BusinessTo most entrepreneurs “growth” is a magic elixir; they are naturally attracted to growth, they love growth—be it in profi ts, sales, or incomes. Investors usually look for fi rms with solid growth records. Also, to most business managers a growing gross national product (GNP) means a stronger economy with more consumer spending, more employment, and more sales and services. There is, therefore, understandable trepidation among those with businesses when they contemplate the prospects of a slowing, or even cessation, of population growth. They fear reduced demand, which in turn means less profi t, smaller dividends, more unemployment, and general economic uncertainty (even though effective demand depends not just on numbers but also on affl uence, the ability to pay).

The impact of population growth on the economy of the United States is assumed to be positive because it has continued for so long. Economic theorists have, however, found it diffi cult to fi nd a direct correlation between population growth and economic well-being in highly industrialized nations. During parts of the nineteenth century population growth was high, yet per capita income growth was modest. On the other hand, in the twentieth century population growth slowed down while the GNP remained high. Among the three economic superpowers—Japan, the United States, and the European Union—only the United States has a signifi cant rate of population growth, and a lack of growth does not seem to have diminished the affl uence of its competitors. Nonetheless, concern remains about the connection between economic growth and prosperity, especially as fer-tility continues to decline and populations grow older. In support of this concern Long-man (2004, 41) noted, “. . . for better or for worse, population growth is still the prime driver of economic growth. Increase in population causes new houses to be built, new cars to be manufactured, and new law offi ces to be built.”

After following similar demographic paths for many decades, trends in Western Europe and the United States began to diverge around 1980. Up until then fertility had



been getting lower in each region, but after 1980 fertility declines continued in Western Europe whereas fertility began a gradual upward trend in the United States. The increase in American fertility was a result of both more births among native-born citizens and more immigration. Many immigrants have come from higher fertility societies, and their fertility in the United States has continued at a higher level than for the American-born population. This has been especially noticeable for the Latino population and for some Southeastern Asian groups as well. One result of the fertility divergence between Western Europe and the United States is its effect on the age distributions of the two populations; by 2050 the average age in the former is predicted to be around 53 and for the latter around 36. In turn, then, Western Europe’s aging population will be more of a burden, whereas America’s younger population is likely to be more innovative.

Labor ForceThe composition and quality of the labor force are important variables for personnel man-agers to consider. During the next few decades the nature of the labor force will be con-siderably different from what it has been in the past. There will be more workers and they will need to be better educated. There will be more minorities in the labor force as well as more females, mothers of young children, and older workers over age 55. Many of these changes in the United States will be direct results of the baby boom.

The supply of workers available for businesses will be the result of two separate trends in the labor force. First is the size of the working age population, and second is the labor force participation rate. Among the most important demographic variables in determining the size of the work force is the age structure of the population. The bulge in the young working force cohort is now progressing through the population, so the number of young people entering the work force will be declining, though earlier projections are going to be off because of rising immigration and higher fertility in places such as California.

At the other end of the work force age spectrum, among those over 55 years of age, important changes will take place. Changing attitudes about retirement could have far-reaching impacts on the corporate world. Can business easily absorb those older workers who decide to continue their careers? Will companies fi nd it harder to promote young workers if retirement ages advance? Will older workers continue to be productive? These are all important questions to personnel managers and are underlain by demographic changes in society. During the 1990s corporate downsizing resulted in the elimination of many jobs held by these workers, leaving them fl oundering to compete for lower-paying jobs with few or no benefi ts.

Labor migration in the future promises to be at least as important as population growth, and it will affect the populations of numerous sending and receiving nations. As Wallerstein (1999, 17) observed, “We shall nonetheless see a rise in the real rate of migration, legal and illegal—in part because the cost of real barriers is too high, in part because of the extensive collusion of employers who wish to utilize such migrant labor.” Illegal immigration alone has become a critical issue among average Americans, yet politi-cians and corporate executives do their best to ignore it. As Bartlett and Steele (2004, 58) discovered, “For corporate America, employing illegal aliens at wages so low few citizens could afford to take the jobs is great for profi ts and stockholders . . . companies are rarely, if ever, punished for it.” This issue can only attract more attention in the years to come.

In 2010 there were an estimated 10.8 million undocumented immigrants living in the United States (Hoefer, Rytina and Baker, 2011). Even though it is illegal to hire an undocumented immigrant, most of these millions are working in the US. It is jobs that attract them. Congress, never quick to solve real problems, is struggling to create new leg-islation that would deal with the problems of undocumented immigration, but at the time

Among the most

important demo-

graphic variables in

determining the size

of the work force is

the age structure of

the population.

Illegal immigration

alone has become a

critical issue among

average Americans,

yet politicians and

corporate execu-

tives do their best to

ignore it.



we are writing this it doesn’t look promising. From building walls to seal off our southern border to giving amnesty to all who have entered undocumented, opinions and emotions run the gamut. There is much sound and fury, but so far little light.

The Education Roller CoasterThe nation’s education system, perhaps more than any other social institution, has been greatly affected by fertility variations. The impact of the postwar baby boom children on the s chools was dramatic, costly, and painful. In the late 1950s and 1960s school enroll-ments soared. The elementary-school-age population (5–13 years) grew from 23 million in 1950 to 37 million in 1970, for example. Secondary schools faced similar problems by the early 1960s, and the high school population doubled in size between 1950 and 1975 (Bouvier, 1980, 21). High school enrollments rose 14 percent in 1957 alone, and a criti-cal shortage in classrooms was evident. Administrators projected a need for an additional 750,000 teachers in three years. This demand caused a rapid increase in school budgets.

Changing Enrollment TrendsSchool planners were totally unprepared for this rapid increase in enrollments. By the time colleges had geared up to graduate enough teachers and massive building programs had produced enough elementary and secondary classrooms, the crest of the baby boom wave was about to leave the K-12 school ages.

The mid-1960s saw enrollments in colleges and universities skyrocket. This increase was a result of both the sheer numbers of baby boomers and the increased proportion of young people going to college. In the 1950s only about 10 percent of those between ages 25–29 had completed at least four years of college. That proportion increased to 16 percent by 1970 and 23 percent by 1980. Between 1957 and 1975 college enrollments increased from 3 million to 11 million, creating a growth industry of its own. The baby boom generation thus became the most highly educated generation in American history (Bouvier and DeVita, 1991, 14).

The major change in school enrollment in the 1970s and 1980s has been a signifi cant increase in nursery and preschool attendance. The percentage enrolled in nursery schools, pre-kindergarten or kindergarten programs, or child-care centers with an “educational” curriculum, increased from 11 percent in 1965 to 38 percent in 1988 (Bianchi, 1990, 30). In 2005 that percent increased to 74.

Another school turnaround occurred. After years of stable or declining enrollments, the school-age population was projected to increase by about 8 percent during the decade of the 1990s. This increase was the result of the baby boom’s children fi lling the elemen-tary and secondary schools across the country (Bouvier and De Vita, 1991, 15); it was also very different from one region to another.

Geography VariationsIn order to understand these educational trends and their demographic causes, it is neces-sary to look beyond national statistics and to understand regional or more local circum-stances. The geographic distribution of the population, as well as spatial differences in vital rates, presents a complicated picture. For example, the decline in births was not uniform across the United States in the 1960s and early 1970s. In some areas the peak in births was attained in 1957, whereas in other areas it was not reached until 1960 (Reinhardt, 1979, 10). Also, the decline in births within states was not uniform, and there were signifi cant differences between metropolitan and nonmetropolitan areas.



These geographic differences, as well as other changes in population distribution, mean that some areas have had dramatic declines in the school-age population, whereas others have still been growing. Many rural areas and urban regions losing population have experienced dramatic declines, but many newly developing suburbs have enrollment increases, as do some inner-city areas. Nursery school attendance is more common in the Northeast than other U.S. regions, and among children who live outside the central cities of metropolitan areas (Bianchi, 1990, 30).

Migration has also had a signifi cant impact on school-age populations. Increases can be seen throughout much of the Sunbelt and the West, with declines in the Midwest and the Northeast. An analysis of college-age students also points out signifi cant spatial dif-ferences, with many Sunbelt and Western states being net importers of college students. Changes in demographic factors can have a signifi cant impact on school planning policy decisions and should be incorporated into the decision-making process at all levels.


population growth and change - kendall hunt … 1 population growth and change 3 percentage rate....

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